Carpet sweepers are known in the art, and one common style of sweeper is a bi-directional carpet sweeper. The sweeper has a brush wheel, a main drive wheel and a housing. To clean a carpet, the housing is moved in either a forward or reverse direction, depending on whether the sweeper is being pushed or pulled. The main drive wheel rotates in the direction of the housing and the brush wheel rotates in a single direction regardless of the direction of the main drive wheel or housing. Accordingly, the sweeper is capable of removing dirt from a carpet regardless of whether the sweeper is being pushed or pulled. The following discloses several of these carpet sweepers and the problems associated with these sweepers.
U.S. Pat. No. 642,172 to Sweitzer discloses a bi-directional sweeper. The brush wheel is controlled by a series of gears connected to a broom handle. The motion of the broom handle affects the configuration of the gears enabling the bi-directional motion.
One problem with Sweitzer is that the handle must be moved to change the configuration of the gears. Accordingly, the handle cannot be removed from the broom and the broom is prohibited from being used as a hand held device.
U.S. Pat. No. 643,634 to Dodd discloses a bi-directional sweeper. The sweeper has a pitman arm that has a first and second ends. The first end is connected to the drive wheel and the second end is capable of controlling the brush wheel. The second end has a set of gear teeth that intersect the spinning axis of the brush wheel. The brush wheel has a pair of pinion wheels that are mounted along the axis of the brush wheel and flank the gear teeth of the pitman arm. Each pinion wheel has a pawl which engages the pinion wheel and allows that pinion wheel to spin in one direction. The resulting rotation of both pinion wheels facilitates spinning of the brush wheel in the same direction, regardless of whether the drive wheel is spinning in the forward or reverse direction.
The problem with Dodd is that both pinion wheels and both pawls must be in line with the brush wheel for the mechanism to operate. The pinion wheels and pawls must be exceedingly thin so as not to diminish the surface area of the brush wheel. The required location of the pinions and pawls makes these components readily susceptible to receiving the infiltration of dirt. The required-size of the pinions and pawls makes these components susceptible to clogging by the infiltrated dirt.
U.S. Pat. No. 879,977 to Morrison, et al. discloses a bi-directional sweeper. The sweeper has a first and second set of drive components located on opposing sides of the housing. Each set of components consists of a drive wheel, a combination of a boss wheel and a pawl, and a set of gears. Each respective boss wheel is adjacent to, and in contact with, the each respective drive wheel. Each respective set of gears is in contact with the respective boss wheel and the brush wheel. The first and second set of components are on opposing ends of the housing for placing the gears outboard of the brush wheel. The sets of components are required to be narrow for maximizing the surface area of the brush wheel.
In Morrison, the when the sweeper is pushed, the first pawl presses against the first boss to activate the first set of drive components. When the sweeper is pulled, the second pawl presses against the second boss to activate the second set of drive components. As a result, the brush wheel spins in the same direction regardless of whether the sweeper is pushed or pulled.
Morrison has a problem in that the sweeper requires two full sets of drive components, where the sets are narrow to maximize the surface area of the brush wheel. The function of each set of components is dependent on a single narrow pawl on that set. Each narrow pawl must absorb the entire stress of operating the sweeper in a single direction. Accordingly, each pawl will suffer fatigue within a relatively short period of time.
U.S. Pat. No. 2,563,189 to Rigby discloses a bi-directional sweeper. The sweeper has two brush wheels, each wheel being capable of rotating in a single direction. Each brush wheel is connected to a respective combination of a boss and a pawl, and each respective boss is engaged upon the selective pivoting of the handle of the sweeper. The challenge with Rigby is that the handle cannot be removed from the broom so that the broom is incapable of being used as a hand held device.
U.S. Pat. No. 3,602,932 to Morris, et al. discloses a bi-directional sweeper. The sweeper has a first and a second brush wheel. The first wheel rotates in the opposite direction from the second wheel and the first wheel rotates when the second wheel is stationary. One problem with Morris is that there are two brushes that require constant cleaning.